Cover DR and armour penetration

[starslayer]

Does armour penetration apply to cover DR; or no?

What about for fantastically high values of armour penetration (like cosmic: ignores defence).

The situation where this came up is as follows:

Enemies are hidden behind stone wall with DR 10, HP 400 (homogeneous); PC shoots wall with imbued bullet doing 2d(200) damage.

I initially ruled 'well just puncturing it would be like over-penetrating a person; so it absorbs HP20 as the bullet sails through'; however pg 408 says 'give the barrier 'cover dr' of DR+HP/4= 70DR in this case, which does not even stop 1 point of the 2d(200) shot.

So how should cover DR be handled when armour penetrators are in play?

[Ulzgoroth]

Cover DR is exactly like any other DR.

That includes cover DR provided by other people in the path of the bullet, walls, and anything else.


Weapons with infinite armor divisors can in fact be used to snipe people through planets, assuming you can handle the aiming.

[Mr Frost]

Originally Posted by starslayer

...however pg 408 says 'give the barrier 'cover dr' of DR+HP/4= 70DR in this case, which does not even stop 1 point of the 2d(200) shot....

As I see it , that makes perfect sense . If a projectile can penetrate half a meter of RHA {the origonal protective value of the glasis of an Abrahms M1 if mamory serves , and those tanks practically ignored the 1970s era 125mm tank gun ammunution Iraq threw at them} , then a mere brick wall will be virtually meaningless as hard cover .

I would still however have it giving the minimum of 1 point {which does make a small difference to 2D} as I'm pretty sure that is how the rules read and it does make sense .

[starslayer]

Originally Posted by Mr Frost

As I see it , that makes perfect sense . If a projectile can penetrate half a meter of RHA {the origonal protective value of the glasis of an Abrahms M1 if mamory serves , and those tanks practically ignored the 1970s era 125mm tank gun ammunution Iraq threw at them} , then a mere brick wall will be virtually meaningless as hard cover .

I would still however have it giving the minimum of 1 point {which does make a small difference to 2D} as I'm pretty sure that is how the rules read and it does make sense .

But that's kind of the point- I'm not sure that a 2d attack even WITH AP 200 SHOULD penetrate a half meter of RHA- simply by feature of it being a half meter thick and weighing hundreds of kilograms. The weapons that do penetrate a half meter of RHA do a huge amount of damage as well as having hefty armour divisors (I think a shaped charge does 6d6*10(10), the absolute 20 hit points I wanted to give to that wall would hardly phase that sort of shot).

It also means that whenever someone uses a super high AP attack should you even roll damage or does it just do 1 point of damage while it sails through the fleshy target as if they were not there (baring a hit to the vitals or brain) and then you calculate over-penetration for everyone along the line of fire until it plummets into the earth, orbits it several times, and stays moored in the core.

[lexington]

Originally Posted by starslayer

Does armour penetration apply to cover DR; or no?

What about for fantastically high values of armour penetration (like cosmic: ignores defence).

The situation where this came up is as follows:

Enemies are hidden behind stone wall with DR 10, HP 400 (homogeneous); PC shoots wall with imbued bullet doing 2d(200) damage.

I initially ruled 'well just puncturing it would be like over-penetrating a person; so it absorbs HP20 as the bullet sails through'; however pg 408 says 'give the barrier 'cover dr' of DR+HP/4= 70DR in this case, which does not even stop 1 point of the 2d(200) shot.

So how should cover DR be handled when armour penetrators are in play?

How did you get the wall absorbing 20HP?

[vierasmarius]

Originally Posted by starslayer

But that's kind of the point- I'm not sure that a 2d attack even WITH AP 200 SHOULD penetrate a half meter of RHA- simply by feature of it being a half meter thick and weighing hundreds of kilograms. The weapons that do penetrate a half meter of RHA do a huge amount of damage as well as having hefty armour divisors (I think a shaped charge does 6d6*10(10), the absolute 20 hit points I wanted to give to that wall would hardly phase that sort of shot).

The problem is that AP (200) is utterly nonsensical in any realistic setting. It's blatantly magical, so of course it goes through walls like magic. If you don't want a 2d attack ignoring solid walls, don't let them make AP 200 attacks.

It also means that whenever someone uses a super high AP attack should you even roll damage or does it just do 1 point of damage while it sails through the fleshy target as if they were not there (baring a hit to the vitals or brain) and then you calculate over-penetration for everyone along the line of fire until it plummets into the earth, orbits it several times, and stays moored in the core.

In a word, no. Roll damage exactly as normal. Even though Cover DR is calculated from HP, it is not the same thing as HP loss. For example, if a sniper shoots through two targets in a row using AP (2) rounds, the Cover DR of the first is halved, but the amount of injury is not. Yes, this means that there are times when a bullet will do more than it's normal damage capacity. The smaller wound channel of AP rounds is already accounted for by their reduced piercing wound modifier.

[Mr Frost]

Originally Posted by starslayer

But that's kind of the point- I'm not sure that a 2d attack even WITH AP 200 SHOULD penetrate a half meter of RHA- simply by feature of it being a half meter thick and weighing hundreds of kilograms. The weapons that do penetrate a half meter of RHA do a huge amount of damage as well as having hefty armour divisors (I think a shaped charge does 6d6*10(10), the absolute 20 hit points I wanted to give to that wall would hardly phase that sort of shot).

It also means that whenever someone uses a super high AP attack should you even roll damage or does it just do 1 point of damage while it sails through the fleshy target as if they were not there (baring a hit to the vitals or brain) and then you calculate over-penetration for everyone along the line of fire until it plummets into the earth, orbits it several times, and stays moored in the core.

It should depend on what powers that armour divisor : if science then give that wall hit point enough to stop it given we can't see how 2D can do that ; if magic then let the shot pass through because a wizard did it™ .

In stories and gaming , Science™ should generally make sense {even though we really know very little about our universe and most of our cherrished assumptions will probably be found out to be as wrong as Platos' 4 elements and Aether theory} whereas magic is , you know , magic .

[Mr Frost]

Originally Posted by lexington

How did you get the wall absorbing 20HP?

He asked it nicely .

[DouglasCole]

Yeah, AD (200) is freakin' magic. That's fine, GURPS can handle it. Just roll 2d-1 and be done with it for each shot that hits.

[Ulzgoroth]

Originally Posted by starslayer

But that's kind of the point- I'm not sure that a 2d attack even WITH AP 200 SHOULD penetrate a half meter of RHA- simply by feature of it being a half meter thick and weighing hundreds of kilograms. The weapons that do penetrate a half meter of RHA do a huge amount of damage as well as having hefty armour divisors (I think a shaped charge does 6d6*10(10), the absolute 20 hit points I wanted to give to that wall would hardly phase that sort of shot).

(200) resembles nothing real that I can think of, but it is very clearly defined. Throwing out that definition on intuition is not a good idea.

Though you may want to consider whether or not you actually think a 2d (200) attack is a good model for whatever it is that you're using that to represent, since you seem to think that it isn't behaving as expected.

Originally Posted by starslayer

It also means that whenever someone uses a super high AP attack should you even roll damage or does it just do 1 point of damage while it sails through the fleshy target as if they were not there (baring a hit to the vitals or brain) and then you calculate over-penetration for everyone along the line of fire until it plummets into the earth, orbits it several times, and stays moored in the core.

I think you're underestimating the thickness of the planet. (200) is a lot, but not that much. However, yes, it will penetrate any normal human pretty much as if they weren't there. Or any normal automobile, or many buildings.

More to the point, though, the attack's effect on the target is governed by it's wounding type, not its armor divisor. As is always the case.